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951.
An energetic solar proton and electron event was observed by particle detectors aboard Explorer 33 (AIMP-1) and OGO-3 during the period July 16–19, 1966. Optical and radio observations of the sun suggest that these particles were produced by a flare which may have occurred on July 16 near the central meridian of the invisible hemisphere. The active region to which the flare is assigned is known to have produced the energetic particle events of July 7 and 28, 1966. The propagation of the particles in the July 16–19 event over the 180° extent of solar longitude from the flare to the earth is discussed, and it is concluded that there must exist a means of rapidly distributing energetic particles over a large area of the sun. Several possible mechanisms are suggested. 相似文献
952.
Andrew S. Tanenbaum John M. Wilcox Edward N. Franzier Robert Howard 《Solar physics》1969,9(2):328-342
One dimensional magnetograph scans have been used to study the 5-min photospheric velocity oscillations and the supergranulation.
The oscillations in wing brightness lead the oscillations in velocity by less than 90° in the photosphere, and about 90° in
the chromosphere, suggesting that they are traveling waves at lower levels and standing waves at higher levels. Downward flows
have been observed to be coincident with the chromospheric network confirming the hypothesis that material is flowing downward
at supergranular boundaries. 相似文献
953.
Richard C. Altrock Laurence J. November George W. Simon Robert W. Milkey Simon P. Worden 《Solar physics》1975,43(1):33-37
Heights of formation of lines that do not exhibit Zeeman splitting are calculated using an LTE, partial non-LTE, and full
non-LTE approach. Non-magnetic (g=0) lines are valuable for velocity investigations in quiet-Sun magnetic field regions, and a knowledge of their formation
heights is useful for obtaining three dimensional velocity profiles in these regions.
Presently at Sacramento Peak Observatory.
Operated by the Association of Universities for Research in Astronomy, Inc., under contract with the National Science Foundation. 相似文献
954.
955.
Verification tests of linear wave propagation models for cases of waves propagating through a refractive focus typically overpredict peak amplitudes in the vicinity of the focus. Using a parabolic equation model for the combined refraction-diffraction of weakly-nonlinear waves [valid for Ursell number Ur < O(1)], we show that, in a particular experiment, much of the discrepancy between laboratory measurements and linear wave model predictions can be accounted for by including the effect of nonlinearity, which is important in the region of the focus. 相似文献
956.
The response function defines the response of line profiles to a depth variation of such atmospheric parameters as velocity, magnetic field and turbulence. The properties of this function are derived and compared with the so-called contribution function.Operated by the Association of Universities for Research in Astronomy, Inc., under contract with the National Science Foundation. 相似文献
957.
958.
Pressure and temperature dependence of the elastic properties of polycrystalline trevorite (NiFe2O4)
Robert C. Liebermann 《Physics of the Earth and Planetary Interiors》1972,6(5):360-365
Ultrasonic pulse-superposition measurements at 298 K as a function of hydrostatic pressure to 3 kb for polycrystalline trevorite (NiFe2O4; 1.0% porosity) yield values of the isotropic elastic properties as shown in the table to the right. 相似文献
959.
960.